691 research outputs found
Mass and momentum transfer by solitary internal waves in a shelf zone
The evolution of large amplitude internal waves propagating towards the shore and more specifically the run up phase over the "swash" zone is considered. The mathematical model describing the generation, interaction, and decaying of solitary internal waves of the second mode in the interlayer is proposed. The exact solution specifying the shape of solitary waves symmetric with respect to the unperturbed interface is constructed. It is shown that, taking into account the friction on interfaces in the mathematical model, it is possible to describe adequately the change in the phase and amplitude characteristics of two solitary waves moving towards each other before and after their interaction. It is demonstrated that propagation of large amplitude solitary internal waves of depression over a shelf could be simulated in laboratory experiments by internal symmetric solitary waves of the second mode
Defragmentation of in-vitro fertilization blastocyst stage embryos leading to rescued blastocyst expansion and clinical pregnancy
Embryo fragmentation, or extrusion of cell fragments, is a naturally occurring phenomenon that may be associated with impaired embryo development, failed implantation and decreased pregnancy rates. Previous studies have shown improvement in clinical outcomes after microsurgery to aspirate these cell fragments from embryos early during the embryo cleavage process. This case series of three patients with infertility showcases the successful application of the defragmentation technique in blastocyst stage embryos after in-vitro fertilization. The timing of defragmentation allows for better identification of those growth-arrested embryos that would benefit from “rescue� defragmentation. All three embryos demonstrated continued expansion and development after defragmentation, and resulted in clinical pregnancies.ECU Open Access Publishing Support Fun
Structural and magnetic dimers in the spin-gapped system CuTe2O5
We investigated the magnetic properties of the system CuTe2O5 by
susceptibility and electron spin resonance measurements. The anisotropy of the
effective g-factors and the ESR linewidth indicates that the anticipated
structural dimer does not correspond to the singlet-forming magnetic dimer.
Moreover, the spin susceptibility of CuTe2O5 can only be described by taking
into account interdimer interactions of the same order of magnitude than the
intradimer coupling. Analyzing the exchange couplings in the system we identify
the strongest magnetic coupling between two Cu ions to be mediated by
super-super exchange interaction via a bridging Te ligand, while the
superexchange coupling between the Cu ions of the structural dimer only results
in the second strongest coupling
The influence of brood chickens by-products processing with probiotic culture starter on change of their functional and technological parameters.
By-products are the potential source of animal protein obtained from brood chickens and egg-laying hens. Certain by-products like gizzards and combs are quite tough and possess low nutritional and biological value due to their high content of connective tissue. Biotechnological processing improves the quality parameters of collagen-containing by-products. In this article a probiotic starter culture of propionic acid bacteria, which have high proteolytic activity, was used to treat the gizzards and combs of brood chickens. Before processing of by-products with starter culture, physical and chemical parameters and the yield of by-products in relation to poultry live weight were analyzed and recorded. 5%, 10% and 15% starter culture were added to the tested samples of chopped by-products, the samples were kept at a temperature of 30 °C, and every 4 hours the following functional and technological parameters were monitored: moisture binding capacity, water holding capacity (MBC and WHC) and yield of the product after heat treatment. The results proved that increase of starter culture amount and longer exposure of by-products to hydrolysis led to decrease of functional and technological parameters values, but for the combs those parameters remained at a sufficiently high level compared to the gizzards, as the gizzards were exposed to more intense hydrolysis than combs. The decrease in the pH value correlated with the dynamics of MBC and WHC changes; and dynamics of the product yield after the heat treatment. Also the stained histological preparations were studied in order to assess the influence of biotechnological processing on by-products microstructure, where significant differences were found in the morphological structure of muscle and collagen fibers of hydrolysates of combs and gizzards exposed to action of bacterial concentrate. The results of rheological studies showed that hydrolyzed chicken combs differed from gizzards; the combs were denser and featured more elastic structure due to a lower degree of hydrolysis by bacterial enzymes. In general, the properties of collagen-containing by-products (muscular gizzards and combs) change significantly after being exposed to enzymes of propionic acid bacteria
Esophageal variceal ligation in the primary and secondary prevention of variceal bleeding
This article is devoted to experience of endoscopic ligation of varices in N.A. Semashko Republic Clinical Hospital. We analyzed the results of ligation in 28 patients treated since February 2013 to March 2016. Selected patients had diagnoses of liver cirrhosis, syndrome of portal hypertension of different origin, 10 (35.5 %) had the history of one or more episodes of bleeding from varicose veins of the esophagus. Endoscopic ligation was performed for patients with varices of grade 3-4 according to J. Paquet classification, grade 3 according to N. Soehendra, K. Binmoeller classification improving primary and secondary prevention of bleeding. The effectiveness of endoscopic ligation as a method of primary and secondary prevention of bleeding from the varices, with subsequent transfer to oral administration of non-selective β-adrenoblockers was evaluated. In the result of the study throughout the entire period of observation we indicated no episodes of esophageal bleeding and established a low rate of recurrence of varices. Those patients who, after the first endoscopic ligation session, followed the recommendations for taking beta-blockers, have a better prognosis and the outcome in relation to patients who have neglected the recommendations. During the first year of follow-up there was one fatal outcome - a man with VHC died as a result of hepatocellular insufficiency
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Rates of lobar atrophy in asymptomatic MAPT mutation carriers.
IntroductionThe aim of this study was to investigate the rates of lobar atrophy in the asymptomatic microtubule-associated protein tau (MAPT) mutation carriers.MethodsMAPT mutation carriers (n = 14; 10 asymptomatic, 4 converters from asymptomatic to symptomatic) and noncarriers (n = 13) underwent structural magnetic resonance imaging and were followed annually with a median of 9.2 years. Longitudinal changes in lobar atrophy were analyzed using the tensor-based morphometry with symmetric normalization algorithm.ResultsThe rate of temporal lobe atrophy in asymptomatic MAPT mutation carriers was faster than that in noncarriers. Although the greatest rate of atrophy was observed in the temporal lobe in converters, they also had increased atrophy rates in the frontal and parietal lobes compared to noncarriers.DiscussionAccelerated decline in temporal lobe volume occurs in asymptomatic MAPT mutation carriers followed by the frontal and parietal lobe in those who have become symptomatic. The findings have implications for monitoring the progression of neurodegeneration during clinical trials in asymptomatic MAPT mutation carriers
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Brain MR Spectroscopy Changes Precede Frontotemporal Lobar Degeneration Phenoconversion in Mapt Mutation Carriers.
Background and purposeThe objective of this study was to longitudinally investigate the trajectory of change in 1 H MRS measurements in asymptomatic MAPT mutation carriers who became symptomatic during follow-up, and to determine the time at which the neurochemical alterations accelerated during disease progression.MethodsWe identified eight MAPT mutations carriers who transitioned from asymptomatic to symptomatic disease during follow-up. All participants were longitudinally followed with an average of 7.75 years (range 4-11 years) and underwent two or more single voxel 1 H MRS examinations from the posterior cingulate voxel, with a total of 60 examinations. The rate of longitudinal change for each metabolite was estimated using linear mixed models. A flex point model was used to estimate the flex time point of the change in slope.ResultsThe decrease in the NAA/mI ratio accelerated 2.09 years prior to symptom onset, and continued to decline. A similar trajectory was observed in the presumed glial marker mI/Cr ratio accelerating 1.86 years prior to symptom onset.ConclusionsOur findings support the potential use of longitudinal 1 H MRS for monitoring the neurodegenerative progression in MAPT mutation carriers starting from the asymptomatic stage
Understanding the Educational Event of the Workshop Format as An Innovative Form of Organization of Educational Activities of Students
В статье рассмотрен метод «Workshop», представлены его структура и отличительные особенности, а также проанализирован опыт участия в мероприятии «Научный Workshop», формат и организационные принципы которого могут быть использованы в процессе обучения, что будет способствовать увеличению учебно-познавательной активности студентов.The article is considered the «Workshop» method, presented its structure and distinctive features, and analyzed the experience of participating in the "Scientific Workshop" event. The format and organizational principles of this method can be used in the learning process, which will increase the educational and cognitive activity of students
Cold-induced changes in gene expression in brown adipose tissue, white adipose tissue and liver
Cold exposure imposes a metabolic challenge to mammals that is met by a coordinated response in different tissues to prevent hypothermia. This study reports a transcriptomic analysis in brown adipose tissue (BAT), white adipose (WAT) and liver of mice in response to 24 h cold exposure at 8°C. Expression of 1895 genes were significantly (P<0.05) up- or down-regulated more than two fold by cold exposure in all tissues but only 5 of these genes were shared by all three tissues, and only 19, 14 and 134 genes were common between WAT and BAT, WAT and liver, and BAT and liver, respectively. We confirmed using qRT-PCR, the increased expression of a number of characteristic BAT genes during cold exposure. In both BAT and the liver, the most common direction of change in gene expression was suppression (496 genes in BAT and 590 genes in liver). Gene ontology analysis revealed for the first time significant (P<0.05) down regulation in response to cold, of genes involved in oxidoreductase activity, lipid metabolic processes and protease inhibitor activity, in both BAT and liver, but not WAT. The results reveal an unexpected importance of down regulation of cytochrome P450 gene expression and apolipoprotein, in both BAT and liver, but not WAT, in response to cold exposure. Pathway analysis suggests a model in which down regulation of the nuclear transcription factors HNF4α and PPARα in both BAT and liver may orchestrate the down regulation of genes involved in lipoprotein and steroid metabolism as well as Phase I enzymes belonging to the cytochrome P450 group in response to cold stress in mice. We propose that the response to cold stress involves decreased gene expression in a range of cellular processes in order to maximise pathways involved in heat production
The Role of the Danish Church in the Fight against the COVID-19 Pandemic and the Significance of This Experience for the Russian Federation
The social responsibility of religious organizations in modern conditions is reflected in a variety of activities carried out by religious institutions and differ depending on both the confessional affiliation of these institutions and the specific structural territorial unit where they take place. The presented work is devoted to a detailed analysis of the peculiarities of the manifestation of one of the directions of social responsibility of the Evangelical Lutheran Church of Denmark (ELCD), associated with minimizing the consequences of COVID-19 on the example of its individual dioceses. The dioceses characterized by the highest proportion of adherents in the population structure (Diocese of Viborg, Ribe, Aalborg and Lolland-Faster) were selected to clearly reflect the trends taking place. The subject of the study is the social activities of the ELCD to mitigate the consequences of COVID-19 for parishioners, the features of the implementation of which are considered on the example of structural units at the regional level. The article substantiates the increased importance of the ELCD in the development of the region, since the designated institution largely assumes the social obligations of the state (duplicates several functions) in connection with the risks of the spread of coronavirus infection. To achieve the goal, methods of analysis of factual and economic-statistical information, comparative comparison were used. The experience of a religious organization in dealing with the consequences of the COVID-19 pandemic is of interest to the public, government bodies and authorities, as well as religious organizations in other countries. The results of the study can be useful in developing a strategy for the development of state-religious relations in Russia, where there are trends of strengthening the social and economic role of religious organizations
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